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Perseverance Rover lands on Mars [video]

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Re: Perseverance Rover lands on Mars [video]

#441

Post by omni »

stargazer-3 wrote: post #404
jessriedel wrote: post #387

Earlier quoted context omitted.

Great video! I am also surprised by the fact that they bring that much mass just to jettison. In theory they could mounted some of the useful mass on a slider/rail system to achieve the necessary adjustment to the mass distribution without dropping mass overall, but apparently it wasn't worth the complexity/volume cost. I'm sort of surprised we don't yet have ML powered "de-accent-ization". His french accent isn't ha…

I, for one, would be uncomfortable with AI removing my accent. I understand it's for other people to understand me better - and I am fine with AI-generated subtitles - but altering the way I speak would reduce the amount of "me" in ways I'm not fully ok with.

What's special about speech that makes this argument apply to speech alteration but not to subtitles? It's a tool to make you easier to understand, not to erase your person.

Re: Perseverance Rover lands on Mars [video]

#442

Post by xaqfox »

saagarjha wrote: post #413
mongol wrote: post #390

Earlier quoted context omitted.

I wonder what a huge Carrington solar storm would do to humanity. If electricity went out everywhere, transformers burned up all over, electronics fried. If this caused transport failures, mass starvation could follow. I really hope a severe solar storm would not be as bad as that and hopefully someone could enlighten me on this.

Killing literally every single human being is not easy. Sure, killing off half of humanity is pretty easy to conceive, but to kill all of humanity it takes a lot more work.

Luckily, we have great minds working on this problem: https://www.appliedeschatology.com/

Re: Perseverance Rover lands on Mars [video]

#443

Post by nippoo »

jessriedel wrote: post #387
michaelwilson wrote: post #297

Earlier quoted context omitted.

It turns out that they took 640lbs (!) of weight to mars to be tossed off at various points during EDL. The video is worth watching if you'd like some more of the nitty-gritty behind the process: https://www.youtube.com/watch?v=W0NakShgbHY

Great video! I am also surprised by the fact that they bring that much mass just to jettison. In theory they could mounted some of the useful mass on a slider/rail system to achieve the necessary adjustment to the mass distribution without dropping mass overall, but apparently it wasn't worth the complexity/volume cost. I'm sort of surprised we don't yet have ML powered "de-accent-ization". His french accent isn't ha…

No need to have a fancy all-new ML algorithm - stick a text-to-speech output on the auto-generated video subtitles and you can set it to whatever language you like.

If the speech recognition / subtitling algorithm can't understand the nuances of the language, that's going to be a problem anyway... accented pronunciation is so multidimensional, you're pretty much going to have to transcribe syllables/phonemes first...

Re: Perseverance Rover lands on Mars [video]

#444

Post by gameswithgo »

jws wrote: post #344
Azrael3000 wrote: post #55

It's a great achievement with some really interesting work done on the landing algorithms with terrain recognition and it seemed to have worked exceptionally well. Looking forward for the next landing in May of the Chinese rover and all the science these robots will produce. Also, the test of Ingenuity, the helicopter, will be very interesting to watch, that could really pave the way for a different exploration style…

Early starships got me thinking: given the high likelihood of a failed starship landing, and maybe having the ability to send one before fully engineering a payload… What would you ballast a starship with for the practice missions? Useful materials which might survive a RUD and aim for someplace near a likely landing zone? If you crash the parts of a milling machine, a lathe, some tooling, some assorted metals stock,…

we playing factorio here?

Re: Perseverance Rover lands on Mars [video]

#445

Post by zo1 »

mikewarot wrote: post #430
george3d6 wrote: post #426

Earlier quoted context omitted.

Because "refine" really means "melt at temperatures ranging from 500 to 4000 degrees celsisu and then extract via various mechanical processes and/or using various reactants which often require gigantic plants to produce and are highly unstable". Basically all of the history of science until 200 years ago was figuring out "mine and extract" and the course of civilization is very much linked with the price & quality o…

We don't have to be efficient, just small and reliable, no matter how slow... if there were enough small machines to turn out enough materials to build new ones faster than the failure rate, then geometric growth wins, and you can build whatever you want, eventually.

It could be something very low-tech even. Just a machine that turns solar-energy + some mechanical power into say mars-dust bricks, non-stop for use in future missions? Maybe something that just keeps digging a perpetually deeper and deeper trench in a straight line so that subsequent missions don't need big drills to find out below-surface samples?

But thinking about it now, I can't envision that we here would be able to come up with something sublime/novel that a huge army of really-smart people haven't already after spending decades thinking about it. Then again, we have a lot of smart people concentrated in this forum, so who knows if a weird/silly conversation triggered by IT-minded people, acts as a catalyst for the engineer-lurkers that see it.

Re: Perseverance Rover lands on Mars [video]

#446

Post by bernulli »

mulmen wrote: post #358
bernulli wrote: post #356

Earlier quoted context omitted.

Yes I understand. Imperial is awesome because you can divide a foot by exactly 2, 3, 4 , and 6, which of course, is the main problem everyone has every day. Metric on the other hand sucks because none of my measurements will ever be nice round numbers. The hardware doesn’t think in base 10, but having more than that in imperial makes it better? Your document lists 12 mass units alone. I rest my case, what could possi…

> Yes I understand. Imperial is awesome because you can divide a foot by exactly 2, 3, 4 , and 6, which of course, is the main problem everyone has every day. Great, we agree. > Metric on the other hand sucks because none of my measurements will ever be nice round numbers. Depends on the situation. Metric units can be useful. > The hardware doesn’t think in base 10, but having more than that in imperial makes it bett…

>> The hardware doesn’t think in base 10, but having more than that in imperial makes it better? >No, it means neither system has an advantage so just pick one. Or invent a new one that allows better hardware utilization.

But one of the systems does have an advantage because it stays in base 10, whereas the other doesn't.

>> Your document lists 12 mass units alone. I rest my case, what could possibly be more logical, convenient, and need less conversion. >I don’t convert, I just pick the unit that fits the problem

But you can't if you just use the `intuitive unit', and that's the whole problem. How would you measure the amount of liquid fuel in, say, the small tank for an attitude control thruster of some probe? How does that add to the overall mass of the whole probe? Or to the force you then need to accelerate it by a certain amount? And now compared to the whole launcher?

In which units do you measure everything going on in a small wind tunnel model, and how do you compare that with the real thing?

Under which conditions do you go from fluid ounces to ounces to cups to pints to quarts to gallons (also note that, again, you not only switch units but bases)?

>Yeah I use the metric system all the time. Just like NASA.

Good for you, it solves all the problems.

Re: Perseverance Rover lands on Mars [video]

#447

Post by suyash »

jvanderbot wrote: post #255
suyash wrote: post #148

Earlier quoted context omitted.

More about Ingenuity https://spectrum.ieee.org/automaton/aerospace/robotic-explor... and it's source code https://github.com/nasa/fprime

That is not Ingenuity's source code, that's the software framework used to link the various software modules. It's generic to any mission / instrument.

correct

Re: Perseverance Rover lands on Mars [video]

#449

Post by matt-attack »

Sharlin wrote: post #171
unanswered wrote: post #167

Something I don't understand: when they say "X is 1 minute from happening", does that mean it's really 1 minute from happening or does that mean "in 1 minute we'll receive the signal that X has happened"? Maybe my question makes more sense in the case of "X is happening right now", because then I should either understand "we infer that X should have happened right about now" or "we have confirmed via signal that X ha…

Yes, those are all Earth Receive Time, that is, when they were saying that eg. entry interface is two minutes away, in reality the rover was already sitting on the surface and we were just waiting for the radio signal to get here.

But aren’t those two events essentially simultaneous in the relativistic sense? That is by some definitions of “simultaneous”?

Re: Perseverance Rover lands on Mars [video]

#450

Post by Evidlo »

onion2k wrote: post #422
mulmen wrote: post #403

Earlier quoted context omitted.

But does anyone say 1/8th centimeter? Seems easier to just drop down to millimeters at that point. Which is fine, but it loses out on the convenience of fractions.

People do say things like 1.25mm, which is 1/8th of 1 cm. Presumably someone who uses Imperial would say 5/128th inches if they wanted to describe something that's equivalent to 1mm?

Most likely they would use mils/thou.

25mils ~ 1mm

Or 1/16in as others have said.

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